High pressure pipe and fitting restraint system

ABSTRACT

A restraint system for use in securing temporary flow lines that include multiple pipe sections, each pair of pipe sections connected together with a fitting or coupling such as a hammer joint coupling. The system includes multiple pluralities of endless loop slings connected end to end with a cow hitch or girth hitch knot. Disconnectable fittings (e.g., shackles) are placed every three or more slings so that easy disassembly is afforded in case of leakage or other failure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/760,956, filed 5 Feb. 2013, which is herebyincorporated herein by reference.

Priority of U.S. Provisional Patent Application Ser. No. 61/760,956,filed 5 Feb. 2013, which is incorporated herein by reference, is herebyclaimed.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

REFERENCE TO A “MICROFICHE APPENDIX”

Not applicable

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to devices for restraining, restricting,or arresting movement of temporary piping such as high pressure pipelineor flow lines during a catastrophic failure. More particularly, thepresent invention relates to a method and apparatus for restraining highpressure pipe and fittings wherein a series of endless loop slings arejoined end to end with hitch type connections (such as a cow hitch,sling hitch, lanyard hitch or other like knot) and wherein each of firstand second lengths of assembled slings are connected end to end withdisconnectable connections (e.g., shackles) that enable service ormaintenance of a selected section of the high pressure piping systemwithout disassembly of all of the endless loop slings, and wherein theassembly of slings and connectors is knotted to the pipeline (e.g., withhalf hitch knots) at selected intervals.

2. General Background of the Invention

In the offshore oil and gas industry, temporary high pressure pipelinesare often employed at or near a drilling platform or drilling rig orupon a deck of a drilling platform or drilling rig. These high pressurepipelines are assembled using couplings which are also high pressurerated. If one of these sections of pipe or coupling that make up thehigh pressure flow line fail or leak, the pipe can violently move,potentially causing injury or death to personnel and/or damage toequipment. For example, pipe sections can come completely apart when afailure occurs.

Patents have issued for restraint systems designed to restrain a flowline or parts thereof. The following are examples of such patents:

U.S. Pat. Nos. 2,746,773; 5,689,862; 6,481,457 (wherein each of thesepatents is hereby incorporated herein by reference).

The '457 Patent is directed to a “Safety Restraint Assembly for HighPressure Flow Line”. The patent is owned by S.P.M. Flow Controls, Inc.of Fort Worth, Tex. (hereinafter “S.P.M.”).

A Society of Petroleum Engineers publication which is identified by thenumeral SPE 24619 and entitled “Restraining System to Help Contain WellFlow Lines and Equipment During Rupture for Increased Safety” was saidto have been prepared for presentation at the 87th Annual TechnicalConferences and Exhibition of the Society of Petroleum Engineers held inWashington, D.C., 4-7 Oct. 1992.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a restraint system for use in securingtemporary flow lines that include multiple pipe sections, each pair ofsections connected together with a fitting such as a pressure holdingcoupling (e.g., a hammer union or coupling).

The present invention thus provides a restraint system for use insecuring temporary flowlines that include multiple pipe sections, eachpair of pipe sections connected together with fittings. Such temporarypiping systems are commonly used in sizes/diameters 2 inch (5.08centimeters), 3 inch (7.62 centimeters), 4 inch (10.16 centimeters) asexamples. The system includes an assembly of polyester round slings,round slings or loop slings (preferably endless loop slings) connectedend-to-end, each sling having end portions that are secured to one ormore other endless slings. The loops or slings can be synthetic roundslings as defined by ASME B30.9. Core yarns of each sling can be of asynthetic fiber. Covers of the slings can be woven from synthetic yarns.The synthetic round slings can be fabricated from core yarns woundtogether with multiple turns and enclosed in a protective cover(s). Thecover and core can be of the same type of material. When the core andcover are of a different type, the thread should be as the same typeyarn as the core. Stitching, if used, should be of the type to preventunraveling.

Disconnectable fittings join one assembly of multiple slings to anotherassembly of multiple slings.

The disconnectable fitting is not a part of a sling.

In one embodiment, the disconnectable fitting can be a shackle.

In one embodiment, each endless sling is wrapped around the pipingsystem at least one 360° wrap.

In one embodiment, there are at least three endless loop slings in eachassembly.

In one embodiment, each endless loop sling assembly encircles a pipesection next to a fitting.

The present invention provides a method for restraining a temporary flowline that includes multiple pipe sections, each pair of sectionsconnected together with a disconnectable coupling.

The method provides first and second pluralities of connected endlesssling loops, each plurality including at least three endless loop slingsconnected end to end with a cow hitch, girth hitch or sling hitch orother hitch knot.

The endless loop slings are connected end to end and connecting eachplurality to another plurality with a disconnectable connector.

In one embodiment, the disconnected connector is not a part of anendless sling.

In one embodiment, the connector is metallic.

In one embodiment, the connector is a shackle.

In one embodiment, the connector is a fitting having two parts, one partthat disconnects from the other part.

The present invention provides a restraint system for use in securingtemporary flowlines that include multiple pipe sections, each pair ofsections connected together with fittings. An assembly of endless loopslings are connected end-to-end, each sling having end portions that aresecured to one or more other endless slings.

Disconnectable fittings join one assembly of multiple endless slings toanother assembly of multiple endless slings;

The disconnectable fitting is not a part of an endless loop sling.

The assembly of flowlines is connected at intervals to the pipe sectionsand fittings using knotted connectors.

In one embodiment, the disconnectable fitting is a shackle.

In one embodiment, each endless sling is tied to the piping system withhalf hitch knots.

In one embodiment, there are between 2 and 12 endless loop slings ineach assembly.

In one embodiment, each endless loop sling assembly is tied to a pipesection next to a fitting.

The present invention provides a method for restraining a temporary flowline that includes multiple pipe sections, each pair of sectionsconnected together with a disconnectable coupling, the system providingfirst and second pluralities of connected endless sling loops.

Each plurality includes at least three endless loop slings connected endto end with a knotted connection.

The slings are connected end to end connecting each plurality to anotherplurality with a disconnectable connector.

The slings are knotted to the flow line at intervals using half hitch orother knotted connections.

In one embodiment, the disconnected connector is not a part of anendless sling.

In one embodiment, the connector is metallic.

In one embodiment, the connector is a shackle.

In one embodiment, the connector is a fitting having two parts, one partthat disconnects from the other part. In one embodiment the two partsare a shackle bow and a shackle pin.

Anchors can be used to anchor the extreme ends of the slings or loops orround slings. Such an anchor can be a pump truck, well head, immovableobject. The connection to the immovable object can be a choke hitch orshackle.

The polyester round slings are used to form a hitch connection parallelto the piping installation, with hitch connections before and after eachpipe connection/swivel and at regular intervals (e.g. five feet (1.524meters)) on straight joints of pipe. At the end of a run of severalslings connected end to end, the last sling is connected to an immovableobject such as a well head or other immovable object using a shackle orlike structural connector.

The present invention includes a restraint system for use in securingtemporary flowlines that include multiple pipe sections, each pair ofsections connected together with one or more fittings. The system caninclude an assembly of multiple endless loop slings connectedend-to-end, one sling having end portions, an end portion secured to oneor more of said other slings with a cow hitch knot connection. Aplurality of disconnectable fittings can each join one assembly ofmultiple slings to another assembly of multiple slings. Thedisconnectable fitting is not a said sling. The slings can be attachedto the assembly of pipe sections and fittings with knots at spaced apartpositions.

In one embodiment, the disconnectable fitting can be a shackle.

In one embodiment, the knot can include a wrap of a said sling aroundthe piping system at least one 360° wrap.

In one embodiment, each sling assembly can include three or more endlessloop slings in each assembly.

In one embodiment, the said knot can secure each endless loop slingassembly to the pipe section encircling the pipe multiple times next toa said fitting.

In one embodiment, each sling assembly can include a sling that connectsto two other side slings with first and second spaced apart cow hitchknots.

In one embodiment, there can be multiple spaced apart fittings and theassembly of endless loop slings encircles a pipe section multiple timesin between two of said spaced apart fittings.

In one embodiment, the assembly of endless loop slings can encircle asaid fitting multiple times and on opposing sides of said fitting.

In one embodiment, the slings can be of differing lengths.

In one embodiment, the slings can be of differing thicknesses.

The present invention includes a method for restraining a temporary flowline that includes multiple pipe sections, each pair of sectionsconnected together with a disconnectable coupling. The method includesproviding first and second sling assemblies, each assembly comprisingmultiple endless sling loops connected to one another. Each slingassembly can include at least three endless loop slings connected end toend, one of the endless loop slings being a middle sling that connectsat spaced apart positions with a girth hitch knot joining one said slingto another said sling. The endless loop slings can be connected end toend connecting each plurality to another plurality with a disconnectableconnector. The slings can be attached to the assembly of pipe sectionsand fittings with knots.

In one embodiment, the disconnectable connector is not a part of anendless sling.

In one embodiment, the connector can be metallic.

In one embodiment, the connector can be a shackle.

In one embodiment, the connector can be a fitting having two parts, onepart that disconnects from the other part.

The present invention includes a restraint system for use in securingtemporary flowlines that include multiple pipe sections, each pair ofsections connected together with fittings. The system can have multipleassemblies of endless loop slings connected end-to-end, each assemblydefined by one sling having an end portion that is secured to one ormore other endless slings with a cow hitch knot. Disconnectable fittingscan join one said assembly of multiple endless slings to anotherassembly of multiple endless slings, wherein the disconnectable fittingis not a said endless loop sling. The system further includes attachingthe assemblies to the flowlines at intervals using a combination ofknotted connectors that each encircle the flowline.

In one embodiment, the disconnectable fitting can be a shackle.

In one embodiment, each endless sling can be tied to the piping systemat with half hitch knots.

In one embodiment, there can be between 2 and 12 endless loop slings ineach assembly.

In one embodiment, each endless loop sling assembly can be tied to apipe section next to a fitting.

The present invention includes a method for restraining a temporary flowline that includes multiple pipe sections, each pair of sectionsconnected together with a disconnectable coupling. The method includesproviding multiple assemblies of connected endless sling loops. Eachplurality can include at least three endless loop slings connected endto end with each sling attached to another said sling with a girth hitchknot. The assemblies can be connected end to end, one assemblyconnecting to another assembly with a disconnectable connector. Themethod can include knotting the slings to the flow line at intervals.

In one embodiment, the disconnectable connector is not a part of anendless sling.

In one embodiment, the connector can be metallic.

In one embodiment, the connector can be shackle.

In one embodiment, the connector can be a fitting having two parts, onepart that disconnects from the other part.

In one embodiment, the slings can be of differing lengths.

In one embodiment, the slings can be of differing diameters.

In one embodiment, the slings can be of a polyester material.

In one embodiment, the slings can be of a synthetic fiber material.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

For a further understanding of the nature, objects, and advantages ofthe present invention, reference should be had to the following detaileddescription, read in conjunction with the following drawings, whereinlike reference numerals denote like elements and wherein:

FIG. 1 is a perspective view of a preferred embodiment of the apparatusof the present invention illustrating one of the loop sling portionsthereof;

FIG. 2 is an elevation view illustrating a part of the method of thepresent invention;

FIG. 3 is an elevation view illustrating a part of the method of thepresent invention;

FIG. 4 is an elevation view illustrating a part of the method of thepresent invention;

FIG. 5 is a fragmentary view illustrating a connection used to join oneendless loop sling to another endless loop sling as part of the methodof the present invention;

FIG. 6 is an fragmentary view illustrating a part of the method of thepresent invention;

FIG. 7 is an elevation view illustrating a part of the method of thepresent invention;

FIG. 8 is an elevation view illustrating a part of the method of thepresent invention;

FIG. 9 is a fragmentary elevation view illustrating a connection of oneloop sling to another loop sling using a shackle;

FIG. 10 is a fragmentary elevation view illustrating a connection of oneloop sling to another loop sling using a shackle;

FIG. 11 is a fragmentary elevation view illustrating a connection of oneloop sling to another loop sling using a shackle;

FIG. 12 is a fragmentary elevation view illustrating a connection of oneloop sling to another loop sling using a shackle;

FIG. 13 is a fragmentary elevation view illustrating a connection of oneloop sling to another loop sling using a shackle;

FIG. 14 is a partial perspective view illustrating the method of thepresent invention, illustrating an anchor at one end portion of a slingassembly;

FIG. 15 is a partial perspective view illustrating the method of thepresent invention, illustrating an anchor at one end portion thereof;and

FIG. 16 is a partial view of a preferred embodiment of the apparatus ofthe present invention illustrating a sling assembly as used with themethod of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-16 show a preferred embodiment of the apparatus of the presentinvention designated generally by the numeral 10 in FIGS. 2-4. Restraintsystem 10 is used to secure a high pressure flow line or pipeline 11that can be comprised of a plurality of pipe sections 12, 13 andfittings 14 (e.g., couplings, valves, elbows, tees or other fittings).

Two (2) pipe sections 12, 13 are usually connected at fitting 14.However, the term “fitting” as used herein should be construed broadlyto include anything that can be part of a piping system or flowline.“Fitting” as used herein includes but is not limited to an elbow, tee,reducer, valve, coupling, hammer union, union, as examples. In such ahigh pressure flow line 11, multiple pipe sections are typicallyconnected end to end with fittings, unions or couplings. The flow line11 can include multiple straight sections 12, 13 of pipe and elbow orbend sections, tee fittings, couplings, unions, and the like. Suchtemporary high pressure flow lines, fittings and pipe joints are wellknown in the art.

A fitting 14 (e.g., a coupling such as a hammer union 14, which iscommercially available) can be used to join a pair of pipe sections 12,13 together (see FIGS. 2 and 8). Such hammer unions, couplings or likefittings 14 are known in the art and commercially available. Coupling orfitting 14 can provide a hammer nut 15 having projections 16 which canbe pounded with a hammer to insure a tight seal for the connection ofcoupling or fitting 14 when it is used to join two pipe sections 12, 13together. An example of a hammer union and seal arrangement can be seenin U.S. Pat. No. 6,764,109 entitled “Hammer Union and Seal Therefor”.U.S. Pat. No. 6,764,109 is hereby incorporated herein by reference.

In FIGS. 5-6, there can be seen a knotted connection, such as a cowhitch or girth hitch knot 18 that joins one endless loop sling 17A toanother endless loop sling 17B and to a third sling 17C (see FIG. 16).The slings 17 can be connected end to end as seen in FIG. 16 to form asling assembly 29 (e.g., two or three or four slings). Each sling 17 hasends 31, 32 and center 33. Every few slings, the connection is with ashackle 23 or other disconnectable connector. The knot 18 of FIGS. 5-6and 16 can be perfected to connect two slings 17A, 17B together byforming a first loop 20 and passing it through a second loop 21 asindicated by arrow 19 and pulling the first loop 20 through the secondloop 21 until knot 18 is formed as indicated by arrow 22. The assembledslings 17A, 17B connected with knot 18 can be seen in FIGS. 5-6 and 16.

Once two or more slings 17 are connected end to end as seen in FIGS. 7and 16, an assembly of such slings 17 (e.g., three slings 17A, 17B, 17Cconnected end-to-end) is connected to another assembly of slings (e.g.,three slings 17A, 17B, 17C connected end-to-end) with a disconnectableconnector such as a shackle 23. Shackle 23 has two separable parts, bow24 and pin 25. Such shackles are commercially available. In thisfashion, if a leak is detected, only two shackles 23 next to or onopposing sides of the leak need be disconnected as opposed to all of theslings 17. This feature enables the disassembly of only a few slingsinstead of the dozens or even hundreds of slings that might be employedto restrain a high pressure pipeline or piping system.

The assemblies of slings 17A, 17B, 17C (e.g., three slings per assembly)are knotted to the pipe 11 and fittings 14 at selected intervals usinghalf hitch or other knots (see FIGS. 2-4 and 7-16). In FIG. 2, an anchor27 is provided that can be part of an immovable object such as wellhead26. In order to install the restraint system 10 of the present inventionon a high pressure flow line 11, pipeline or piping system, one endportion of a sling assembly 29 is attached to anchor 27 of wellhead 26.FIGS. 2 and 3 illustrate such an attachment. A half hitch or cow hitchknot 18 can be used to attach an assembly of slings 17A, 17B, 17C asshown in FIG. 16 to the anchor 27 shown in FIGS. 2 and 3. End 31 islooped through the center of end 32 as illustrated by arrows 30 in FIG.2. The knotted connection to anchor 27 is designated by the numeral 34in FIG. 3.

Once an assembly of slings 17A, 17B, 17C is connected to anchor 27 atconnection 34, arrows 38 illustrate that the assembly 29 of slings isconnected to the high pressure flow line 11 at intervals. At eachconnection to the pipeline 11, a knot can be used such as a hitch orhalf hitch knot 35. In FIG. 3, two half hitch or hitch knots 35 areused, one on each side of fitting 14 which fitting is an elbow in FIG.3. For a length of pipe or section of pipe 12 or 13, half hitch or hitchknots 36 can be used at intervals (e.g., every five (5) feet (1.524meters)) designated by the numeral 28 in FIG. 3. In FIG. 3, two morehitches or half hitch knots 37 are used on opposing sides of a fitting14 which is a hammer union.

In FIGS. 4 and 7-9, the installation of an assembly 29 of endless loopslings 17A, 17B, 17C can be seen. Assembly 29 attaches to piping system11 wherein knots 35, 36 and 37 having been completed. Once a first slingassembly 29 of for example two or three or more slings is affixed to thepiping system 11 as shown in FIGS. 3 and 4, one sling assembly 29 of aplurality of slings 17 is then attached to another sling assembly 29 ofa plurality of slings 17 using shackles as shown in FIG. 16. In thisfashion, only one or two shackles 23 need be disconnected should a leakoccur. User's could then repair the damaged pipe section 11 or 12 or thedamaged fitting 14 and then attach a sling assembly or assemblies 29with shackles 23.

FIGS. 10-13 show an alternate method of attaching one loop sling 17A toanother loop sling 17B using shackle 23. In FIGS. 10-13, a first loopsling 17A is connected to a second loop sling 17B by routing the firstloop sling 17A through the open center 33 of the second loop sling 17Bas illustrated by arrow 39 in FIG. 10. An end 31 of the loop sling 17Ais then fastened to the sling 17A using shackle 23 as shown in FIGS.11-13.

FIGS. 14 and 15 show an alternate anchoring arrangement wherein theanchor 41 connects to the piping system or pipe line 11 at connection42. In FIGS. 14 and 15, fitting 14 such as a hammer union is closelyspaced to connection 42. A sling assembly 29 or sling 17 is connected tothe pipe line 11 on opposing sides of the fitting or hammer union 14with a shackle 23 connecting one portion of the sling 17 or slingassembly 29 to another portion of the sling or sling assembly 17, 29 inorder to perfect an attachment of the sling assembly 29 to the pipe line11 itself for providing an anchor at one end portion of the slingassembly 29. The sling assembly is attached to the piping system or pipeline 11 using hitch knots or half hitch knots 35, 36, 37 as with theembodiment of FIG. 4.

The following is a list of parts and materials suitable for use in thepresent invention:

PARTS LIST: PART NUMBER DESCRIPTION 10 restraint system 11 high pressureflow line/pipe line 12 pipe section 13 pipe section 14 coupling/hammerunion/fitting/elbow/tee 15 hammer nut 16 projection 17 endless loopsling 17A first loop sling 17B second loop sling 17C third loop sling 18cow hitch knot/girth hitch knot/sling hitch knot/knotted connection 19arrow 20 first loop 21 second loop 22 arrow 23 shackle/disconnectableconnector 24 bow 25 pin 26 wellhead 27 anchor 28 distance 29 slingassembly 30 arrow 31 loop end portion 32 loop end portion 33 open center34 connection to anchor 35 hitch or half hitch knot 36 hitch or halfhitch knot 37 hitch or half hitch knot 38 arrow 39 arrow 41 anchor 42connection

All measurements disclosed herein are at standard temperature andpressure, at sea level on Earth, unless indicated otherwise. Allmaterials used or intended to be used in a human being arebiocompatible, unless indicated otherwise.

The foregoing embodiments are presented by way of example only; thescope of the present invention is to be limited only by the followingclaims.

1. A restraint system for use in securing a temporary flowline thatincludes multiple pipe sections, each pair of sections connectedtogether with one or more fittings, the system comprising: a) anassembly of multiple flexible restraining slings connected end-to-end,one sling having end portions, a said end portion secured to one or moreof said other slings; b) a plurality of disconnectable fittings thateach join one assembly of multiple slings to another assembly ofmultiple slings; c) wherein the disconnectable fitting is not a saidsling; and d) the slings attached to the assembly of pipe sections andfittings with knots at spaced apart positions, each knot encircling thetemporary flowline.
 2. (canceled)
 3. The restraint system of claim 1wherein the knot includes a wrap of a said sling around the temporaryflowline at least one 360° wrap.
 4. The restraint system of claim 1wherein each said sling includes a loop portion.
 5. The restraint systemof claim 1 wherein the said knot secures each sling to the pipe sectionencircling the pipe multiple times next to a said fitting.
 6. Therestraint system of claim 4 wherein each sling assembly includes a slingthat connects to two other slings with first and second spaced apartknots.
 7. The restraint system of claim 1 wherein there are multiplespaced apart fittings and the assembly of endless loop slings encirclesa pipe section multiple times in between two of said spaced apartfittings.
 8. The restraint system of claim 1 wherein the assembly ofslings encircles a said fitting multiple times and on opposing sides ofsaid fitting.
 9. The restraint system of claim 1 wherein the slings areof differing lengths.
 10. The restraint system of claim 1 wherein theslings are of differing thicknesses. 11-15. (canceled)
 16. A restraintsystem for use in securing temporary flowlines that include multiplepipe sections, each pair of sections connected together with fittings,the system comprising: a) multiple slings connected end-to-end, onesling having an end portion that is secured to one or more other slingswith a knot; b) disconnectable fittings that join one said assembly ofmultiple slings to another assembly of multiple slings; c) wherein thedisconnectable fitting is not a said endless loop sling; and d)attaching the assemblies to the flowlines at intervals using acombination of knotted connectors that each encircle the flowline. 17.The restraint system of claim 16 wherein the disconnectable fitting is ashackle.
 18. The restraint system of claim 16 wherein each sling is tiedto the temporary flowline with half hitch knots.
 19. The restraintsystem of claim 16 wherein there are between 2 and 12 slings in eachassembly.
 20. The restraint system of claim 16 wherein each sling istied to a pipe section next to a fitting.
 21. A method for restraining atemporary flow line that includes multiple pipe sections, each pair ofsections connected together with a disconnectable coupling, comprisingthe steps of: a) providing multiple slings, at least one said slingincluding a loop portion; b) each plurality including at least threeendless loop slings connected end to end with each sling attached toanother said sling with a knot; c) the slings connected end to end, onesling assembly connecting to another sling assembly with adisconnectable connector; and d) knotting the slings to the flow line atintervals with knots that each encircle the temporary flow line.
 22. Themethod of claim 21 wherein the disconnectable connector is not a part ofan endless sling. 23-25. (canceled)
 26. The method of claim 21 whereinthe slings are of differing lengths.
 27. The method of claim 21 whereinthe slings are of differing diameters.
 28. The method of claim 21wherein the slings are of a polyester material.
 29. The method of claim21 wherein the slings are of a synthetic fiber material.
 30. A restraintsystem for use in securing a temporary flowline that includes multiplepipe sections connected together with fittings comprising: a) anelongated flexible restraining member; b) the elongated flexiblerestraining member connecting to the temporary flowline with multipleknots that each encircle the temporary flowline; and c) wherein theelongated flexible member abuts the temporary flowline in between knots.